Implantable neurostimulation systems have proven therapeutic in a wide variety of diseases and disorders. For example, Spinal Cord Stimulation (SCS) techniques, which directly stimulate the spinal cord tissue of the patient, have long been accepted as a therapeutic modality for the treatment of chronic neuropathic pain syndromes, and the application of spinal cord stimulation has expanded to include additional applications, such as angina pectoralis, peripheral vascular disease, and incontinence, among others. Spinal cord stimulation is also a promising option for patients suffering from motor disorders, such as Parkinson's Disease, Dystonia and essential tremor.
An implantable SCS system typically includes one or more electrode-carrying stimulation leads, which are implanted at a stimulation site in proximity to the spinal cord tissue of the patient, and a neurostimulator implanted remotely from the stimulation site, but coupled either directly to the stimulation lead(s) or indirectly to the stimulation lead(s) via a lead extension. The neurostimulation system may further include a handheld patient programmer to remotely instruct the neurostimulator to generate electrical stimulation pulses in accordance with selected stimulation parameters. The handheld programmer may, itself, be programmed by a technician attending the patient, for example, by using a Clinician's Programmer (CP), which typically includes a general purpose computer, such as a laptop, with a programming software package installed thereon.
Thus, programmed electrical pulses can be delivered from the neurostimulator to the stimulation lead(s) to stimulate or activate a volume of the spinal cord tissue. In particular, electrical stimulation energy conveyed to the electrodes creates an electrical field, which, when strong enough, depolarizes (or “stimulates”) the neural fibers within the spinal cord beyond a threshold level, thereby inducing the firing of action potentials (APs) that propagate along the neural fibers to provide the desired efficacious therapy to the patient.
Hypertension is a health problem affecting millions of people, requiring considerable expenditure of medical resources as well as imposing significant burdens on those who suffer from this condition. Hypertension generally involves resistance to the free flow of blood within a patient's vasculature, often caused by reduced volume stemming from plaque, lesions, and the like. Because blood vessels do not permit easy flow, the patient's heart must pump at higher pressure. In addition, reduced cross-sectional area results in higher flow velocity. In consequence, a patient's blood pressure may enter into the range of hypertension i.e. greater than 140 mm Hg systolic/90 mm Hg diastolic.
It has been recognized that the kidneys play a key role in blood pressure regulation, and a number of hypertension treatment approaches have focused on the kidneys, providing a number of pharmaceutical compounds aimed at promoting blood to flow through these organs. One treatment option has been to destroy some or all of the nerves innervating the kidneys through ablation, a process in which an ablation electrode, carried in an instrument such as an endoscope, is introduced into a patient's vasculature and navigated to a position within the renal artery. Electrical energy, operating at radio frequencies, is applied to the electrode, resulting in destruction of the renal nerves. This process, of course, is irreversible and carries the possibility of undesirable side effects. The process is nonetheless effective in combating hypertension.
Thus, a need remains for a process that can ameliorate hypertension without permanently affecting the renal nervous system.